1. Field of the Invention
This invention relates to mechanical linkage arrangements for generating substantially pivotal motion about a point which is not pivotally attached.
2. Description of the Prior Art
Magnetic bubble wafers must be tested in the presence of two magnetic fields: a biasing magnetic field for creating the magnetic bubble domains in the wafer and a scanning magnetic field for moving the domains within the wafer. The wafer, therefore, is mounted on an elongated member and inserted in a narrow horizontal slit between two substantial magnet structures. Once the wafer is in position between the magnets immediately above and below it, the wafer is rotated in the horizontal plane so as to become aligned with the scanning magnetic field. The elongated member upon which the wafer is mounted protrudes from the magnet structures and is mounted on an assembly which permits the member to move in the horizontal plane in such a manner as to generate substantially pivotal motion in the horizontal plane about the point where the magnetic bubble wafer is mounted. Since there is insufficient space in the narrow confines between the magnet structures to provide a mechanical pivotal attachment at a point near the wafer, horizontal pivoting of the wafer must be accomplished by the application of forces upon the elongated member at points removed from the point where the wafer is located.
An obvious prior art method for generating pivotal motion about a point which is not secured to a pivot employs an elongated member extending radially from the point where the remote pivotal motion is desired. The member is mounted upon one or more arcuate tracks which are concentric about the remote point. Although this mechanism produces true pivotal motion about the remote point in the center of the curvature of the track, there exist substantial drawbacks which elevate its cost and complexity to a prohibitive level in applications where the arcuate track and the mounting means for the longitudinal member are situated an extended radial distance from the remote point. A costly lathe with a protracted radial arm is required to manufacture the track. Moreover, a precisely fitted roller-mounting arrangement is required to permit motion of the elongated member upon the track while maintaining tolerable radial alignment.
It is, therefore, an object of this invention to improve structures for generating substantially pivotal motion about an unaffixed point on the axis of a radial member.
It is another object of this invention to produce a simple and economical mechanism for generating precisely controllable angular motion about an unaffixed point.